The Laboratory for Cell Analysis (LCA) provides instrumentation and expertise in flow and image cytometry for NIH sponsored researchers at the University of California, San Francisco. The LCA relies on an aging, heavily modified, FACStar Plus for cell sorting. Recently, users have been hampered by the technical limitations of the FACStar Plus and by its increasing failure rate. Since the technical staff of the LCA are operating at full capacity, time lost to service affects all cytometry users since the staff are diverted from other tasks. Decreasing reliability of the current instrumentation decreases the confidence of the user community in the facility and in the data generated therein. In addition, the FACStar Plus does not support electronic pulse shape based sorting or bit-mapped gating now requested by an increasing number of users. We request in this application, funds to replace the aging FACStar Plus with th FACS Vantage Cell Sorter by Becton Dickinson Immunocytometry Systems. The new system will include three lasers: an Innova Model 306 six-watt argon-ion laser, a Model 70 Spectrum laser, and a 633 nm HeNe laser all manufactured by Coherent. This instrumentation will allow improved multi-parameter quantitative measurements, analysis and sorting rates of up to 20,000 cells per second at greater than 97 percent purity, seamless computer network integration with our current environment for faster off-line data processing, an aerosol containment system for viable human cell sorting experiments under temperature controlled conditions, six PMTs for multiple fluorophores, a more robust laser setup providing a greater combination of excitation wavelengths, and faster instrument reconfiguration. The last point is critically important, as the LCA will move in April 1997, into the new Cancer Center Research Building at the UCSF Mt. Zion Campus. This new multi-disciplinary center will house a larger core of LCA users specializing in Cancer genetics, Cancer Biology and Molecular Therapeutics. These diverse users will demand efficient, flexible cell analysis and sorting. Principle applications will involve rare event sorting of human and mouse bone marrow stem cells for studies on in utero transplantation strategies, isolation of cancer micrometastases for molecular characterization by fluorescence in situ hybridization, sorting of transfected cell lines, in particular for expression cloning of scavenger receptors or physiological response to agonist or drug exposure, and sorting for microarray-based analysis of gene expression and relative DNA sequence copy number. A total of 39 researchers representing 44 NIH research grants will be served by this system.